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11.
快速提取分离八角茴香油的新方法 总被引:1,自引:0,他引:1
将回流提取法、水蒸气蒸馏法、快速提取法对八角枝叶或干果中八角茴香油提取进行了比较,并确定八角枝叶或干果中八角茴香油的最佳提取方法和条件。结果表明,快速提取法比回流提取法、水蒸气蒸馏法提取效率高,快速简便。快速提取法提取八角茴香油的最佳条件为:干果原料与水比为1∶6,提取回流时间为2 h,产品收率达12.78%,且含八角茴香脑90.83%。 相似文献
12.
锥—46抑制[^3H]次黄嘌呤掺入伊氏锥虫核酸的研究 总被引:1,自引:1,他引:1
用液体闪烁计数法对锥—46的抗锥虫作用的机理做了初步研究。发现T-46与Berenil很相似,均可显著抑制[~3H]次黄嘌呤掺入伊氏锥虫,抑制作用与浓度及时间呈正相关。T-46和Berenil对DNA合成的IC_(60)分别为1.33和1.73μg·ml~(-1)。本实验还提示T-46抗锥虫作用可能与损伤DNA模板有关。 相似文献
13.
不同来源微粒子孢子间血清学关系的比较研究 总被引:1,自引:4,他引:1
应用玻片凝集法和酶标抗体法比较了几种不同来源微粒子孢子间的血清学关系,包括本所保存的家蚕微粒子孢子(BmN.b),从安徽绩溪和江苏东台的饲养蚕中收集到的微粒子孢子和从四川收集到的蓝叶虫(phyllobrotiacarmataBaly)微粒子孢子。结果表明,绩溪、东台微粒子孢子与BmN.b之间具有相同的血清学关系,而蓝叶虫微粒子孢子与BmN.b之间无血清学关系。 相似文献
14.
One polyclonal antibody against florfenicol and thiamphenicol was produced and a competitive ELISA was developed for the detection of florfenicol and thiamphenicol in swine feed. The ELISA gave a 50% inhibiting concentration of 1.02 ng/mL for florfenicol. For swine feed fortified with 0.05 to 3.0 mg/kg, the interassay recoveries of florfenicol and thiamphenicol ranged from 86.4 to 118.6%, whereas intraassay recoveries of both drug ranged from 90.1 to 126.5% with less than 15% CV. Results obtained from HPLC-tandem mass spectrometry indicated this ELISA procedure could be used as a convenient method for rapid screening of florfenicol and thiamphenicol in swine feed. 相似文献
15.
Silvia Pietschmann Katrin Hoffmann Michael Voget Ulrich Pison 《Veterinary research communications》2009,33(6):489-505
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological
profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the
in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial
activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence
microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was
0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold
resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined
their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal
and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents
against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these
pathogens are involved. 相似文献
16.
牛副结核检疫中的非特异性干扰 总被引:2,自引:0,他引:2
给犊牛接种各种分枝杆菌,然后以副结核PPD进行变态反应试验,观察各分枝杆菌感染对副结核变态反应的干扰;从各种分枝杆菌感染牛群采取血清进行副结核ELISA检测,以观察各分枝杆菌血清对牛副结核ELISA的干扰。结果:多种分枝杆菌,特别是鸟胞内分枝杆菌、瘰疬分枝杆菌的感染可干扰副结核变态反应;部分结核牛血清干扰副结核ELISA的检测 相似文献
17.
Awareness of animal influenza and its prevention and control is important for ensuring livestock health, production and welfare. In China, a country stereotyped as a major source of emerging zoonotic infectious diseases, research on the public understanding of animal influenza is limited to the Han, the main ethnic group. The present qualitative study in Southwest China investigated awareness of animal influenza among the Dai, an ethnic minority. The participants (15 men and 10 women, ages 18–83) were smallholder farmers of pigs and poultry in rural areas of Jinghong, Xishuangbanna, Yunnan Province. A mixture of interviews and group discussions took place in homes and villages. The participants were asked about their knowledge of avian influenza (H7N9), swine influenza (H1N1), precautions taken to protect against influenza, procedures when animals were sick and perceived risk of animal influenza. The data were analysed following coding and thematic analysis. The findings demonstrated a limited understanding of animal health and welfare among participants. Specifically, they were largely unaware of animal influenza (H7N9, H1N1) including its causes, symptoms, prevention and treatment. The farmers were also uninformed of the risks they faced and unknowingly engaged in behaviours which increased direct or indirect exposure to infected animals, a risk factor for human infection. They also reported poor usage of veterinary services. In order to guarantee the health, welfare and production of their livestock, immediate action is needed to enable Dai smallholder farmers to prevent and respond to animal influenza effectively and timely. 相似文献
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20.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献